Stoker



F. L BUFF May 2, 1933.

STOKER Filed Deb.

14, 1931 3 Sheets-Sheet l May 2, 1933.

F. L. BUFF ST'OKER Filed Dec. 14, 1931 3 Sheets-Sheet 2 INVENTOR.

ATTORNEY.

- FranlrLBuff F. L. BUFF May 2, 1933.

STOKER Filed Dec. 14, 1931 5 Sheets-Sheet 3 .m Q kN INVENTOR. Frank L Buff 1 BY 2/? jw I ATTORNEY.

Patented May 2, 1933 PATENT OFFICE rm 1.. am, or wrcma, Kansas s'rom I Application filed December 14, 1881. Serial 1T0. 580,825.

My invention relates to improvements in stokers. p The object of my invention is to provide a worm conveyorhaving a feeder to control the flow of fuel as conveyed into a furnace.

A further object of my invention is to provide a simple and efficient means to control m the rotation of the feeder thru the medium of a gear ratio intermittently operated and to lo vary the speed of the same.

' A still further object of my invention is to provide an exhaust for accumulated gases in the housing of the worm conveyor and feeder, returning the same to the furnace.

A still further object of my invention is to provide a stoker that is motor driven, all of which is inexpensive, simple to install, and eflicient in service.

A still further object of my invention is to provide a safety device whereby the rotation of the worms will cease independent of the power driving elements actuating the same.

These and otherpbjects will hereinafter be more fully explained, reference being had to the accompanying drawings formin a part of this s cification, and in which 1i e characters W111 apply to like parts in the different views, and in which Fig. 1 is a sectional view longitudinally of the conveyor housing.

Fig. 2 is a plan view of the stoker.

Fig. 3 is an enlarged detail sectional view thru the gearing.

, Fig. 4 is a sectional view taken on line 44 in Fig. 3.

Fig. 5 is a side view of the stoker.

Fig. 6 is an end view of the stoker.

Fig. 7 is an enlarged sectional view showing the head and socket between the Worm con- 40 vey or and the worm gear.

if. 8 is a rear elevation of the variable spee mechanism, parts removed for convenience of illustration.

My invention herein disclosed consists of a stoker comprising a tubular housing l thru which bituminous fuel is conveyed to the fire pot 1, the operation of which is later described. A second housing 2 is secured to the outer end of the first said housing. The last said housing is arranged for a worm rotatable therein, and further functions as a support for the hopper 3 mounted thereon. A third housing 4 attached to and in working relation to housing 2, and in which gear elements are trunnioned, the last said housing being oil tight for continuous lubrication.

Rotatably arranged in housing 1 is a worm conveyor 5, the shaft 5' extending into housin 2.

Axially aligned and coupled to a shaft 6 to m which a ring gear 7 is secured as rotating means thereforthru the medium of a worm ear 8 driven by an electric motor 9 carried y an extension 10 from housing 4 positioned in working relation to said worm gear. 05 On the end of shaft 6 that is adjacent the said worm shaft 5' is a socket 11 secured thereto, the said socket ispreferably hexagon in form and adapted to receive a hexagon head 12 fitting snugly but removable. The i said head is integral with the shank portion 13 and has on the outer end thereof a stud 14 that is insertable within the bore 15 that is axially positioned in shaft 5 and rotatable therein, but secured against rotation by a pin 16 diametrically passing thru the shaft and stud, the purpose of which isthat should the worm conveyor 5 be stalled against rotation the pin 16 will shear off without interrupting the drive mechanism, and furthermore so.

this method will preserve against destruction to the worm conveyor as well as the other parts of the mechanism.

Rotatably arranged in the upper portion of housin 2 and in working relation to the conveyor 1s a worm 17 as a feed gauge for fuel to the conveyor, the said worm conveys fuel such as finely broken coal that is stored in the hopper 3 by driving the same to an opening 18 communicating with the outer end of the said worm conve or, which in turn conveys the fuel to the e pot.

The last said worm feeder is arranged on a sleeve 19 that rotatably engages on a shaft 20 trunnioned in housing 2 and has on the outer end thereof a'gear as rotating means therefor, but later described. Diametrically passing thru said sleeve and shaft is a pin 21 that carries the worm in rotation with the shaft until by some irregularity the worm may be stopped, and to avoid-damage thereto, the pin will shear, the shaft being free to rotate, 7

feeder and worm conveyor are The worm actuated thru the medium of a series of gears consisting of a gear 22 that is secured to the end of the feeder worm shaft 20 as rotating means therefor and a similar gear 23 trunnioned on a hub 24' that inwardly extends from the wall of housing 3 and integral therewith. The last said gear 23 has a pin 25 outwardly extendin from one side thereof to engage between t e teeth of gear 22, moving it step by step at each rotation of the gear 23.

i Other similar pins may be inserted in the unoccupied apertures 25, the said apertures threaded to receive the threaded end pprtlon of the pins. The last said gear ing rotated by any number of ins 26, 27, 3Q 28, 29, 30, and 31 that are selective y arranged to vary the speed ratio as desired, by en aging one additional pin at a time, whic in turn varies the quantit of fuel delivered from the hopper 3 to t e conveyor 5. The speed of the latter being equal to that of the mug gear 7 and rotatable therewith, and being so arranged, the fuel delivery into the combustion chamber is with greater rapidity than the delivery of fuel from the hopper to the conveyor 5, through the medium of the said feeder. Y Y

Spaced around the hub of the ring-gear and extending transversely therethru 1s a plurality of pin elements heretofore referred to by the numerals 26, 27, 28, 29, 30, and 31. The extension of the ins adjacent the train of gears vary in lengt the projection on the other side being equal and having a notch in close proximity to the end of each pin to snugly engage on a ring 32 that slidably engiiliges on shaft 6 and rotatable therewith thru t e medium of a diametrically positioned pin 33. The said pin secured to the ring and slidable longitudinally in slot 34 diametrical- 1y passing thru the shaft and extendin a s ort distance longitudinally thereof. The

sliding movement of the ring and pin at? tached thereto is controlled by a screw 35 threadedly engaging in the hollow of shaft 00 6, the said screw having a hand wheel 36 on the outer end as mani ulating means therefore. Note that the sald screw is hollow and hav' a flangp 37 circumscribing an aperture .whic a reduced portion 38 of shaft Q5 39 extends. The outer end of the reduced portion has a nut 40 threadedly engaging thereon, said nut adapted to slide longitudinally in the hollow of the screw 35.

Between the nut and the flange is positioned a coil compression spring 41, and a similar spring 42 between the flange and shoulder of the shaft 39, by which means when the shaft 39 is moved longitudinally in either direction by the screw, a flexible tendency is attained for the purpose of yielding should any one of the pins contact with the side of the teeth prior to entering the space therebetween, but free to move therein as the ring gear rotates.

Spaced along the upper side of shaft 39 is a plurality of notches 42' in which a ball 43 will seat as the said shaft moves longitudinally, the ball being tensioned by spring 44 attached to shaft 6 as shown in Fig. 3, by which means the said pins are stationarily positioned to engage or disengage the same consecutively with gear 23 to vary the speed ofsaid gear which in turn will rotate gear 22 one step per revolution of 'gear 23, and to insure proper engagement of pins 2631 in-.

clusive and pin 25 between the teeth of gears respectively, I have arranged a spring actuated detent for each of said gears. The detent comprising an arm 45 pivotally secured to a hub 46 that is secured to the side wall of housing 4. Wound on the hub is a spring .47, one end of which is secured to the housing, the other end is secured to the arm as tensioning means for snug engagement of roller 48 that is'trunnioned on the outer end of said arm, the said roller seating between the teeth of the ear as accurate positioning means for the said pins to mesh properly at each rota-' tion or moment of engagement. It will be understood thatthemoment of idleness of each gear is secured in proper position by the said roller engagement between the teeth to which position they are accurately moved, and should the spaced movement be varied, the rolling tendency actuated by the spring pressure will properly position the gear as the tendency of the said rollers is to move from the point of the teeth seating therebetween.

Secured to one side of the housin 4 is a fan housing 49 in which is rotata ly arranged a fan secured to the journal 50 of the motor. Extending from the fan housing to thefurnace is a duct 51, by which means a forced draft thru the combustion chamber is supplied. I have also arranged a pipe 52 as communicating means between housing 2 andthe fan housing, by which means gas accumulation within said housing 2 will exhaust thru duct 51 thru the medium of fan action returning the same to the combustion chamber.

My stoker herein disclosed is arranged to pulsatively deliver fuel from the hopper to the worm conveyor and age the quantity of fuel desired by manipu ation of the hand .gear of a stoker conveyor, a power actuated ring gear, a plurality of pins 'slidably engaging thru the said gear and being spaced from and around the shaft of the gear, and an annular ring secured to one end of the pins, the other ends thereof varying in extension in consecutive order, and means to move the pins longitudinally for partial and entire engagement of the extended end portion with the teeth of a gear to vary the speed ratio thereof, a pair of gears and a worm feeder, one gear secured to the feeder shaft, the other gear positioned in working relation to the pin elements, and the first said gears; the last said gear having pins laterally extending from one side and adapted to engage with the teeth of the other gear to pulsatively rotate the same.

2. In a stoker feed actuating means comprising a motor driven ring gear, the gear having a pluralityof pins concentric to the bearing thereof and spaced therearound, one

end of the pins aligned and connected by a ring, the pins varying in length, a toothed gear trunnioned in working relation to the pins, flexibly arranged means to move the pins longitudinally for engagement in consecutive order with the teeth of the gear, and means to stationarily stop the pins as moved toward the gear as variable speed control, a worm conveyor rotatable with the ring gear, and a worm feeder for the conveyor, a toothed gear on the shaft of the worm feeder, the gear in working relation to the second said gear, the said gear having a pin to engage with the teeth of the last said gear rotating the same step by step at each rotation of the second said gear, a spring actuated detent for each of the last said gears to station the same for accurate engagement of the pins with the teeth of their respective gears.

3. In a stoker of the class described comprising a housing for a worm conveyor, a

worm feeder and a hopper thereon, and a train of gears, a worm conveyor and a power actuating ring gear to rotate the worm, a

worm feeder in working relation between the hopper and the outer end of the warm conveyor, a toothed gear on the worm feeder shaft, and a spring actuated detent to engage with the teeth as positioning means during periods of idleness of the gear, another ar having a pin outwardly extending om the side thereof to engage with the teeth of the worm feeder gear to move the same step by step, and a spring actuated detent as positioning means during periods of idleness of the gear, a plurality of pins slidabl arranged thru the hub of the ring gear an equally spaced from and around the shaft of the gear, the extension of the pins to engage with the last said toothed gear as the pins are moved to engagement therewith in consecutive order selecting the desired feed ratio of the worm feeder, and means to move the pins longitudinally.

In testimony whereof I afiix my signature.

FRANK L. BUFF. 

